Nowadays, mobile electronic devices such as mobile phones, personal digital assistants (PDAs), laptop computers, MP3 players, and so on, are in widespread use around the world. While a lot of progress has been made in making smaller electronic devices, there is more and more demand for higher quality and greater serviceability of these mobile electronic devices. Much has been gained from the miniaturization of electronic components and the development of more efficient batteries; in only a couple of decades, mobile communications systems have gone from analogue to digital, and at the same time the dimensions of the communication terminals have gone from briefcase-size to the pocket-size phones of today. Mobile electronic devices are also getting smaller and smaller for even more portability and convenience, while at the same time becoming increasingly capable of performing more advanced functions and services, both due to the development of the devices and the network systems.
This evolution comes with a number of conflicting requirements which are all considered to be an important factors for the end customer. Basically, the device should be as small and light-weight as possible. Furthermore, it should provide more and more advanced functions, have a long battery life, and have a user-friendly interface. Still, there is only so much space in an electronic device, and, in order to be competitive the elements of the device must be carefully designed, assembled and packaged.
While for convenience sake, it is often desirable that these devices be small and lightweight, they still need to possess a certain structural strength so that they will not be damaged in normal handling and occasional drops. Thus, usually built into such devices are structural parts whose primary function is to provide strength and/or rigidity and/or impact resistance to the device, and perhaps also provide mounting places for various internal components of the device and/or part or all of the mobile electronic device case (outer housing). Because of the strength and/or rigidity requirements for these members they are usually made of metal, sometimes a low density metal such as magnesium or aluminum. However use of metals for these parts has drawbacks. Some of these less dense metals such as magnesium are somewhat expensive, and manufacturing the often small and/or intricate parts needed is expensive. The use of metals also sometimes limits design flexibility.
While synthetic resins can overcome some of the limitations of metals such as making intricate parts and lower density, but typical they do not usually have the strength and/or stiffness to be structural parts in mobile electronic devices. As a result, improved structural parts for mobile electronic devices are needed.
US 2010/0291381 relates to structural members for portable electronic devices comprising synthetic resin compositions whose surface is coated at least partially by a metal. A long list of synthetic resins is disclosed.
Indeed, polymer compositions have been used for a long period in the manufacture of mobile electronic devices. Polyamides such as Nylon 6 or Nylon 6,6, and polyesters such as PET or polyolefins have been widely used.
However, as various technologies evolve and improve at a very high pace, the commodity resins exemplified above do not fulfill the market needs anymore. The manufacturing technology must therefore evolve and improve to meet the increased manufacturing demands. These increased demands include, as explained above, lighter and smaller structures but with comparable or even improved overall properties. This miniaturization thus involves the use of higher performance materials for the manufacture of parts of mobile electronic devices (such as structural parts).
The main properties required for the manufacture of parts of mobile electronic devices include good flow properties, high impact strength, high stiffness (and in particular high flexural modulus), good elongation properties and chemical resistance (and in particular resistance to acid environments). Also, in some instances, if the structural parts of mobile electronic devices have complicated shapes that may warp during formation, as in injection molding, it may be advantageous to use a synthetic resin composition which is specifically designed to have low warpage.
However, there is a great demand to reduce the overall costs of the mobile electronic devices as well and the price of the high performance materials should also be therefore maintained within acceptable ranges.
Therefore, a new mobile electronic device and structural parts thereof are desired in order to overcome the above-described shortcomings.